1650420661 has 4 divisors (see below), whose sum is σ = 1663019424. Its totient is φ = 1637821900.

The previous prime is 1650420659. The next prime is 1650420677. The reversal of 1650420661 is 1660240561.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1660240561 = 7 ⋅237177223.

It is a cyclic number.

It is not a de Polignac number, because 1650420661 - 2¹ = 1650420659 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1650420691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6299185 + ... + 6299446.

It is an arithmetic number, because the mean of its divisors is an integer number (415754856).

Almost surely, 2^1650420661 is an apocalyptic number.

It is an amenable number.

1650420661 is a deficient number, since it is larger than the sum of its proper divisors (12598763).

1650420661 is a wasteful number, since it uses less digits than its factorization.

1650420661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12598762.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 1650420661 is about 40625.3696721642. The cubic root of 1650420661 is about 1181.7661622775.

The spelling of 1650420661 in words is "one billion, six hundred fifty million, four hundred twenty thousand, six hundred sixty-one".